diff --git a/poky/documentation/ref-manual/faq.xml b/poky/documentation/ref-manual/faq.xml
index d94cb32..98ae0a9 100644
--- a/poky/documentation/ref-manual/faq.xml
+++ b/poky/documentation/ref-manual/faq.xml
@@ -1,6 +1,7 @@
 <!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"
 [<!ENTITY % poky SYSTEM "../poky.ent"> %poky; ] >
+<!--SPDX-License-Identifier: CC-BY-2.0-UK-->
 
 <chapter id='faq'>
 <title>FAQ</title>
diff --git a/poky/documentation/ref-manual/migration.xml b/poky/documentation/ref-manual/migration.xml
index affc8b9..d3d5b16 100644
--- a/poky/documentation/ref-manual/migration.xml
+++ b/poky/documentation/ref-manual/migration.xml
@@ -1,6 +1,7 @@
 <!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"
 [<!ENTITY % poky SYSTEM "../poky.ent"> %poky; ] >
+<!--SPDX-License-Identifier: CC-BY-2.0-UK-->
 
 <chapter id='migration'>
 <title>Migrating to a Newer Yocto Project Release</title>
diff --git a/poky/documentation/ref-manual/ref-classes.xml b/poky/documentation/ref-manual/ref-classes.xml
index f8920d8..ab12373 100644
--- a/poky/documentation/ref-manual/ref-classes.xml
+++ b/poky/documentation/ref-manual/ref-classes.xml
@@ -1,6 +1,7 @@
 <!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"
 [<!ENTITY % poky SYSTEM "../poky.ent"> %poky; ] >
+<!--SPDX-License-Identifier: CC-BY-2.0-UK-->
 
 <chapter id='ref-classes'>
 <title>Classes</title>
diff --git a/poky/documentation/ref-manual/ref-devtool-reference.xml b/poky/documentation/ref-manual/ref-devtool-reference.xml
index 11f7399..6c3ccc3 100644
--- a/poky/documentation/ref-manual/ref-devtool-reference.xml
+++ b/poky/documentation/ref-manual/ref-devtool-reference.xml
@@ -1,6 +1,7 @@
 <!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"
 [<!ENTITY % poky SYSTEM "../poky.ent"> %poky; ] >
+<!--SPDX-License-Identifier: CC-BY-2.0-UK-->
 
 <chapter id='ref-devtool-reference'>
     <title><filename>devtool</filename> Quick Reference</title>
diff --git a/poky/documentation/ref-manual/ref-features.xml b/poky/documentation/ref-manual/ref-features.xml
index 294b297..8cab5ec 100644
--- a/poky/documentation/ref-manual/ref-features.xml
+++ b/poky/documentation/ref-manual/ref-features.xml
@@ -1,6 +1,7 @@
 <!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"
 [<!ENTITY % poky SYSTEM "../poky.ent"> %poky; ] >
+<!--SPDX-License-Identifier: CC-BY-2.0-UK-->
 
 <chapter id='ref-features'>
     <title>Features</title>
diff --git a/poky/documentation/ref-manual/ref-images.xml b/poky/documentation/ref-manual/ref-images.xml
index 1f96186..aaeda55 100644
--- a/poky/documentation/ref-manual/ref-images.xml
+++ b/poky/documentation/ref-manual/ref-images.xml
@@ -1,6 +1,7 @@
 <!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"
 [<!ENTITY % poky SYSTEM "../poky.ent"> %poky; ] >
+<!--SPDX-License-Identifier: CC-BY-2.0-UK-->
 
 <chapter id='ref-images'>
     <title>Images</title>
diff --git a/poky/documentation/ref-manual/ref-kickstart.xml b/poky/documentation/ref-manual/ref-kickstart.xml
index 1128bd5..45db1c0 100644
--- a/poky/documentation/ref-manual/ref-kickstart.xml
+++ b/poky/documentation/ref-manual/ref-kickstart.xml
@@ -1,6 +1,7 @@
 <!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"
 [<!ENTITY % poky SYSTEM "../poky.ent"> %poky; ] >
+<!--SPDX-License-Identifier: CC-BY-2.0-UK-->
 
 <chapter id='ref-kickstart'>
 <title>OpenEmbedded Kickstart (<filename>.wks</filename>) Reference</title>
diff --git a/poky/documentation/ref-manual/ref-manual-customization.xsl b/poky/documentation/ref-manual/ref-manual-customization.xsl
index c58dd90..3181f61 100644
--- a/poky/documentation/ref-manual/ref-manual-customization.xsl
+++ b/poky/documentation/ref-manual/ref-manual-customization.xsl
@@ -1,4 +1,6 @@
 <?xml version='1.0'?>
+<!--SPDX-License-Identifier: CC-BY-2.0-UK-->
+
 <xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns="http://www.w3.org/1999/xhtml" xmlns:fo="http://www.w3.org/1999/XSL/Format" version="1.0">
 
   <xsl:import href="http://downloads.yoctoproject.org/mirror/docbook-mirror/docbook-xsl-1.76.1/xhtml/docbook.xsl" />
diff --git a/poky/documentation/ref-manual/ref-qa-checks.xml b/poky/documentation/ref-manual/ref-qa-checks.xml
index 424a19c..0071e4a 100644
--- a/poky/documentation/ref-manual/ref-qa-checks.xml
+++ b/poky/documentation/ref-manual/ref-qa-checks.xml
@@ -1,6 +1,7 @@
 <!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"
 [<!ENTITY % poky SYSTEM "../poky.ent"> %poky; ] >
+<!--SPDX-License-Identifier: CC-BY-2.0-UK-->
 
 <chapter id='ref-qa-checks'>
 <title>QA Error and Warning Messages</title>
diff --git a/poky/documentation/ref-manual/ref-release-process.xml b/poky/documentation/ref-manual/ref-release-process.xml
index 5efe174..87f5308 100644
--- a/poky/documentation/ref-manual/ref-release-process.xml
+++ b/poky/documentation/ref-manual/ref-release-process.xml
@@ -1,6 +1,7 @@
 <!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"
 [<!ENTITY % poky SYSTEM "../poky.ent"> %poky; ] >
+<!--SPDX-License-Identifier: CC-BY-2.0-UK-->
 
 <chapter id='ref-release-process'>
 <title>Yocto Project Releases and the Stable Release Process</title>
diff --git a/poky/documentation/ref-manual/ref-structure.xml b/poky/documentation/ref-manual/ref-structure.xml
index 27f17dd..8588e9c 100644
--- a/poky/documentation/ref-manual/ref-structure.xml
+++ b/poky/documentation/ref-manual/ref-structure.xml
@@ -1,6 +1,7 @@
 <!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"
 [<!ENTITY % poky SYSTEM "../poky.ent"> %poky; ] >
+<!--SPDX-License-Identifier: CC-BY-2.0-UK-->
 
 <chapter id='ref-structure'>
 
diff --git a/poky/documentation/ref-manual/ref-style.css b/poky/documentation/ref-manual/ref-style.css
index 7077e4b..622ceb8 100644
--- a/poky/documentation/ref-manual/ref-style.css
+++ b/poky/documentation/ref-manual/ref-style.css
@@ -1,4 +1,7 @@
 /*
+
+   SPDX-License-Identifier: CC-BY-2.0-UK
+
    Generic XHTML / DocBook XHTML CSS Stylesheet.
 
    Browser wrangling and typographic design by
diff --git a/poky/documentation/ref-manual/ref-system-requirements.xml b/poky/documentation/ref-manual/ref-system-requirements.xml
index 7a11ec2..43e217c 100644
--- a/poky/documentation/ref-manual/ref-system-requirements.xml
+++ b/poky/documentation/ref-manual/ref-system-requirements.xml
@@ -1,6 +1,7 @@
 <!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"
 [<!ENTITY % poky SYSTEM "../poky.ent"> %poky; ] >
+<!--SPDX-License-Identifier: CC-BY-2.0-UK-->
 
 <chapter id='ref-manual-system-requirements'>
 <title>System Requirements</title>
diff --git a/poky/documentation/ref-manual/ref-tasks.xml b/poky/documentation/ref-manual/ref-tasks.xml
index 011e0d7..5b09b3f 100644
--- a/poky/documentation/ref-manual/ref-tasks.xml
+++ b/poky/documentation/ref-manual/ref-tasks.xml
@@ -1,6 +1,7 @@
 <!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"
 [<!ENTITY % poky SYSTEM "../poky.ent"> %poky; ] >
+<!--SPDX-License-Identifier: CC-BY-2.0-UK-->
 
 <chapter id='ref-tasks'>
 <title>Tasks</title>
diff --git a/poky/documentation/ref-manual/ref-terms.xml b/poky/documentation/ref-manual/ref-terms.xml
index 722fa7e..d2605c6 100644
--- a/poky/documentation/ref-manual/ref-terms.xml
+++ b/poky/documentation/ref-manual/ref-terms.xml
@@ -1,6 +1,7 @@
 <!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"
 [<!ENTITY % poky SYSTEM "../poky.ent"> %poky; ] >
+<!--SPDX-License-Identifier: CC-BY-2.0-UK-->
 
 <chapter id='ref-terms'>
 <title>Yocto Project Terms</title>
diff --git a/poky/documentation/ref-manual/ref-variables.xml b/poky/documentation/ref-manual/ref-variables.xml
index 657f6cf..9fe744a 100644
--- a/poky/documentation/ref-manual/ref-variables.xml
+++ b/poky/documentation/ref-manual/ref-variables.xml
@@ -1,6 +1,7 @@
 <!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"
 [<!ENTITY % poky SYSTEM "../poky.ent"> %poky; ] >
+<!--SPDX-License-Identifier: CC-BY-2.0-UK-->
 
 <!-- Dummy chapter -->
 <chapter id='ref-variables-glos'>
diff --git a/poky/documentation/ref-manual/ref-varlocality.xml b/poky/documentation/ref-manual/ref-varlocality.xml
index 54524d5..a2436fb 100644
--- a/poky/documentation/ref-manual/ref-varlocality.xml
+++ b/poky/documentation/ref-manual/ref-varlocality.xml
@@ -1,6 +1,7 @@
 <!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"
 [<!ENTITY % poky SYSTEM "../poky.ent"> %poky; ] >
+<!--SPDX-License-Identifier: CC-BY-2.0-UK-->
 
 <chapter id='ref-varlocality'>
     <title>Variable Context</title>
diff --git a/poky/documentation/ref-manual/resources.xml b/poky/documentation/ref-manual/resources.xml
index afe8e28..4899b2e 100644
--- a/poky/documentation/ref-manual/resources.xml
+++ b/poky/documentation/ref-manual/resources.xml
@@ -1,6 +1,7 @@
 <!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"
 [<!ENTITY % poky SYSTEM "../poky.ent"> %poky; ] >
+<!--SPDX-License-Identifier: CC-BY-2.0-UK-->
 
 <chapter id='resources'>
 <title>Contributions and Additional Information</title>